Is there a project management software for Ubuntu like Microsoft Project?

I can also suggest planner . It's available in Ubuntu software-center.

TaskJuggler is really powerful but also a bit harder to use and is not available in Software Center.

You can try RationalPlan. They have several project management products and starting with version 4.2 it is also available in the Ubuntu Software Center. And RationalPlan Single is even free on any Linux.

There are many tools that are web-based and which are very usable through modern web browsers available for Ubuntu, like Firefox and Chromium/Google Chrome. Some are open source and you can install them on your own server, others are provided as Software as a Service, and will --- in most cases --- be provided on a subscription basis. These 'web applications' may provide a pretty comprehensive feature set similar to that of Microsoft Project.

If you are looking for a desktop application that resembles Microsoft Project, is free and open source, you could try OpenProj or GanttProject. They both have some of the features Microsoft Project provides, but opinion varies as to whether they can be considered suitable alternatives.

There is ]project-open[ as a multi-project server, that integrated with OpenProj/Project Libre and many other tools in order to form an open-source project management stack.